I have 5 total plants, and 2 of them (Bullrider strain) have started to develop brown spots along the veins. Some of the leaves are taken over by the brown spots at the tip of the leaf and curling at the ends. The leaves are also really crispy. Its affecting mostly the middle topish growth. I am using 400 watt HPS, 4th week of flowering, using floraNova every 3rd watering, watering everyday to every other day with reverse osmosis water. The lights are about 10-12 inches away from plants. Im not sure what it is and could really use some insight. Thanks a lot!